The fights co-headlined “Adrenaline IV: Sylvia vs. Riley,” which took place in front of an estimated crowd of 2,000 at the Mid-America Center in Council Bluffs, Iowa. The night’s main card aired live on HDNet.

Although looking in questionable shape at a less-than-svelte 287 pounds, Sylvia had little trouble with his opponent. The former UFC heavyweight champion, fighting for the first time since his embarrassing nine-second knockout loss to 48-year-old boxer Ray Mercer in June, continually battered Riley with one-two combinations and quick strikes from the clinch.

Sylvia finally ended it when he clipped Riley with a left hand that sent the Ohio-based fighter crashing to the mat. The referee called a halt to the bout at 2:32 of the first round.

The victory was Sylvia’s first in nearly two years; following a unanimous-decision win over Brandon Vera at UFC 77 in October 2007, the former worldwide top-10 heavyweight suffered three consecutive losses, all via stoppage.

Meanwhile, Alexander, a Nebraskan who received arguably the night’s biggest ovation, fed off the crowd’s energy and instantly went to work on his opponent’s legs. A quick succession of low kicks wobbled Pendergarst, and Alexander rushed in to deliver a series of knees to the body once he sensed the damage.

Pendergarst ultimately crashed to the mat and covered up to protect himself. Alexander, who moved up to heavyweight for the fight, briefly followed with punches before the referee called a stop to the lopsided affair at 1:51 of the first round.

As MMAjunkie.com (www.mmajunkie.com) reported after Alexander’s booking for the Adrenaline event, the popular fighter remains under contract to the UFC. However, with three consecutive losses since he splashed onto the UFC scene with violent knockouts of Keith Jardine and Alessio Sakara, Alexander needed a victory, something that’s eluded him for the past two years.

Pendergarst, meanwhile, continues his oh-so-brutal skid. “The Tank” earned a shot in the UFC after launching his career with an 8-3 record. However, since his loss to Antoni Hardonk at UFC 65, Pendergarst has floundered with five straight losses and 11 defeats in his past 14 fights.

Also picking up victories on the night’s undercard were two UFC vets. Forrest Petz (15-7), just 2-6 since a win over Sammy Morgan in his August 2006 octagon debut, topped fellow ex-UFC fighter Chad Reiner (21-9) in a lopsided bout. Petz did damage with early blows, and a winded Reiner never recovered. A big right hand put Reiner on the mat and forced a TKO stoppage at 2:28 of the first round.

Joe Vedepo (8-3), meanwhile, moved to 8-1 in non-UFC bouts with a swift and stunning 14-second knockout of Webster Farris (2-1). The Iowa-based fighter, who competed for the first time since a 0-2 stint in the UFC, connected on a right hand that instantly knocked Farris out cold and left him struggling to regain consciousness.

As the UFC 189 tour made its last stop in Dublin, featherweight champ Jose Aldo was met with a torrent of abuse from the Irish fans. It might have been unpleasant, but it might also have been just what he needed.